<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>IFC</title>
    <style>
        /*IFC的元素会在一行中从左至右排列*/
        span{
            font-size: 30px;
            background-color: pink;
            /*width: 200px;/*行级标签不识别宽高*/
            /*display: inline-block;/*如果要让行级标签识别宽高必须用display设成块级标签*/
        }
        strong{
            font-size: 16px;
            background-color: green;
            vertical-align: top;
        }
        .box{
            float: left;
            font-size: 50px;
        }
        div{
            display: inline;
        }
    </style>
</head>
<body>
    <span>span</span>
    <strong>strong</strong>
    <em class="box">box</em>
    <div>div</div>
</body>
</html>